There are many situations in which a cable must be clamped to prevent longitudinal displacement of the cable. For example, winch-driven cables are used to haul logs in the logging industry. It is often necessary to temporarily clamp the cable to prevent it from moving along its longitudinal axis while logs are attached to one end of the cable or removed therefrom. In the marine industry, tug boats use cables as tow lines for hauling barges and the like. While a barge is under tow, the tow line must be clamped to prevent intermittent forces from being transmitted along the cable to the tug boat's cable winching apparatus. In various other industries, support platforms are raised or lowered on cables which must sometimes be rapidly and reliably clamped to prevent movement of the cables or platform; for example to ensure the safety of men working beneath the platform.
The prior art has evolved a variety of cable clamping mechanisms. For example, U.S. Pat. No. 4,874,152 issued Oct. 17, 1989 discloses a cable gripping block for suspension bridge cables and the like in which a pair of cable clamping blocks are disposed in a wedge configuration to clamp a cable and prevent it from moving longitudinally. The cable is released by pulling it longitudinally away from the narrow end of the wedge configuration. In the present invention, the cable is released by moving one of a pair of wedges, which together force the cable clamping jaws against the cable.